Boiler



oct. 18, 1949. J, D, PIERCE 2,485,536

BOILER Filed Nov. 23, 1944 4 sheets-sheet 1 Oct. 18, 1949.

J. D. PIERCE r-:TAL

BOILER Filed Nov. 25, 1944 4 Sheets-Sheet 2 c., "Il W www, W" su I Oct. 18, 194'9. .1. D. PIRcv Erm.

BILER 4 Sheets-Sheet 3 Filed Nov. 25, '1944 Oct. 18, 1949. 1. D. PIERCE ETAL 2,485,536

,BOILER Filed Nov. 2:5, 1944 4 4sheets-sheet 4 Patented Oct. 18, 1949 nomia Joseph D. Pierce, Chicago,

Towner, Oak Lawn, Ill., assignors i and Charles E. to Crane Co.,

Chicago, Ill., a corporation of Illinois Application November 23, 1944, Serial No. 564,844

1 Claim.

This invention relates to a boiler. More particularly, it relates to the type embodying a small low capacity round boiler suitable for automatic firing with oil, gas or anthracite coal, and which possesses exceptionally high eiciency and loW Weight ratio due to its novel construction as hereinafter described.

It is an object generally to provide a heat generator for small homes in which a large part of the heating surface is directly exposed to the ame.

More particularly, it is an important object of this invention to provide a boiler in which its improved performance results from the combination of a relatively large amount of primary heating surface in the form of a luted combustion chamber, entirely Water jacketed, and a water backed heat trap formed by utilizing the dome of the boiler as a secondary heating surface with suitable integrally cast fins to direct the ow of the gases over the heating surfaces and ultimately through the baiiled flue outlet to the chimney.

It is a further important object to provide a device in which there is relatively low stack temperature, high heat transmission and efhciency.

Another important object is to provide a very compact boiler having a low Weight ratio in pounds of cast iron per square foot of output, particularly as compared to the conventional type of sectional boiler heretofore considered.

Another important object is to provide a boiler having a one-piece construction in which the machining required is reduced to a minimum and in which the manufacturing cost is relatively low.

A further important object is to provide a boiler in which a substantially tortuous form of baffle in the smokehood directs the oW of hot gases-and products of combustion across the top of the boiler, thus using the latter portion as a secondary heating surface.

Another object is to provide a boiler sufficiently small and compact so as to permit its installation under work cabinets in utility rooms or even in kitchens.

Other objects and advantages of the construction will become more readily apparent in proceeding with the specication read in light of the accompanying drawings, in which Fig. l is an exterior front elevation of a boiler embodying our invention.

Fig. 2 is a vertical section taken on the line 2-2 of Fig. l.

Fig. 3 is a plan view of the boiler with the cover removed to show one form of baille.

Fig. 4 is a sectional View taken on the line 4-4 oi Fig. 2.

Fig. 5 is a fragmentary perspective View of the top of the boiler showing exteriorly the manner in which the cover and the ue outlet are applied.

Fig. 6 is a sectional View taken on the line 6-6 of Fig. 2.

Fig. '7 is a top view showing a modified form of heat trap.

Fig. 8 is a further modied form of heat baille.

Referring now to Fig. 1, the cast boiler casing I is mounted upon the base 2 which may be either in the form of integral legs or else a cylindrical shell may be used for housing the refractory -3 shown in dotted lines and having a central aperture 4. Within the latter aperture the burner pot 5 or any suitable combustion equipment may be extended with the burner portion proper 6 projecting Within the lire chamber I'2 of the boiler. Obviously, depending upon whether oil burning, gas burnin-g or anthracite burning devices are used with the boiler, the manner in which the type of burner just described is mounted Will vary in size and shape. The term boiler or furnace is used interchangeable throughout this description.

At its lower portion adjacent to the support 2 the boiler is provided with an aperture 1 having suitable lugs 8 for mounting the conventional access door (not shown). At its lower portion the boiler is furnished with the respective connections 9 for the return and at the top II for the outlets to provide for the conventional circulation of the heated fluid within the boiler to a heating system (not shown).

As shown more clearly in Fig. 2, the interior of the nre chamber I2 is made with substantially vertical extended flutes I3, preferably but not necessarily tapering toward the upper portion and thereby varying in their relative capacities for the water at different levels, as shown by comparing Figs. 4 and 6. Certain of the iiutes extend inwardly, as indicated at I4, and converge toward the center to form the aperture I5 (Fig. 2) at the upper dome portion of the boiler. Within the chamber I6 the novel heat trap is provided consisting substantially of the vertical extending walls or baffle arrangement I1, as shown more clearly in Fig. 3. The effect of such construction is to thereby provide for the elongated travel of the gases of combustion as indicated by the arrows then leading to the smoke outlet I8. Thus the heat trap is provided With Water jacketed side walls and the top ofthe dome of the boiler or furnace is also Water backed or jacketed, resulting in higher e'iciencies. The heat trap just described, of course, need not necessarily assume the detailed form described but may take the varied forms such as those modifications shown in Figs. 7 and 8. Therefore it is not the intention to be limited to the specific forms of bales described in connection with Figs. 3, 7 or 8.

It will now become apparent that by the combination of the increased amount of area of surface within the combustion chamber l2 by employment of the fluted Walls plus the novel means of trapping the heat at the upper portion of the boiler after it leaves the oriiice I and reaches the heat trap I6, unusual high thermal efliciency is obtainable in a relatively small type of boiler. The boiler is easily assembled upon its supporting base, and at its upper portion, as shown more clearly in Fig. 5, a suitable smoke outlet I9 is attached to the side of the boiler for conducting combustion gases from the heat trap chamber I6 above which a cover 2| relatively snugly fitting is applied, resting preferably upon the top edges of the baffles.

Thus it will be apparent that there has been developed a low capacity boiler suitable for automatic ring in which the heating' efficiency is relatively high, especially when considering its adaptability to small size boilers or furnaces. It should also be understood that many variations may be made in the construction and arrangement of the fluted Walls in the combustion chamber and therefore it is the desire not to be limited other than as determined by the prior art when considering the appended claims.

We claim: A

A substantially round boiler, having a smoke outlet and a combustion chamber, the said chamber having its outer limits defined by vertically uted water jacketed walls converging at their upper portion to form the periphery of an aperture to provide for the escape of the hot products of combustion from the said chamber, the said boiler having a secondary heat transfer chamber communicating with the said aperture and having a iioor comprising the top portion of the said Water jacketed combustion chamber, the said heat transfer chamber having water jacketed side walls, the latter walls being extended integral portions of the walls of the said combustion chamber and being provided with a series of substantially vertical partitions integral With the said chamber floor and forming a tortuous path for the products of combustion and thereby providing a heat trap therefor.

' JOSEPH D. PIERCE.

CHARLES E. TOWNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 282,567 Richardson Aug. 7, 1883 430,589 Page June 17, 1890 1,127,078 Nieberding Feb. 2, 1915 1,869,709 Nystrom Aug. 2, 1932 2,077,776 Schmitt Apr. 20, 1937 

